Scissors having handles which lie on substantially the same axis as the cutting blades are well known. The disadvantage of such a design is that the operator's hand must be bent at the wrist during operation, which easily leads to fatigue. Modifications of this basic design have the handles at an obtuse angle with respect to the scissor blades in order to decrease the bend in the operator's wrist. Nevertheless, with either the basic or modified design, the handles must be pivoted with respect to each other to effect cutting. Moving the handles while cutting, particularly in the modified device where the scissor blades are at an angle with regard to the scissor blades, is difficult for the operator. Additionally, in order to support the scissor blades and provide a more even cut, it is preferable to place the material being cut on a flat surface. Moreover, with either design, the edge of the material being cut defines an axis which bisects the operator's hand. This makes it difficult to align the blades and maintain a straight cut.
There is, therefore, a need for scissors that do not require as great an effort to operate and which provide an even cut even without placing the material to be cut on a flat surface. Additionally, it would be more comfortable for the operator to have a device where, during cutting:
(i) the operator's hand can be located on one side of the material being cut rather than on either side of the edge of the material; PA0 (ii) the operator's hand can extend straight out from the arm and not be bent down from the wrist; and PA0 (iii) the operator can continue a cut which has been started by merely pushing the device through the material without pivoting the handles or the blades. PA0 (i) allows the operator's hand to be located on one side of the material being cut; PA0 (ii) allows the operator's hand to extend straight out from the wrist during operation; PA0 (iii) allows a cut to be continued once started without pivoting of the blades; and PA0 (iv) allows a relatively short lower axial dimension, and still allows cutting through thick or difficult to cut material.
Of the scissors known to Applicants, Seeberger, U.S. Pat. No. 2,326,178, discloses shears or scissors wherein a handle extends at an acute angle transverse to the pivot axis of the blades, and an actuating lever extends at a slightly more acute angle forwardly of the handle. The lever pivots with respect to the handle behind the pivot point of the blades. A forwardly extending portion of the lever is connected to an extension 7 which is part of a movable blade. The pivot point of the blades 2 is located at the front of the extension 7, forwardly of the pivot point of the actuating lever.
Branske, U.S. Pat. No. 2,776,535, discloses a lawn edger with an oscillating blade which is actuated by forcing an upright handle downwardly. An arm 43 is pivotally connected to a tightening screw 44 of a clamp 45, and the clamp is attached to the handle. The arm 43 is also pivotally attached to the upper blade. Thus, downward movement of the handle causes the arm 43 and the upper blade to also move down, which closes the blades.
West German Document No. 124,783 by Rudolph discloses shears having an upper blade which pivots with respect to the lower blade. A lever attaches the upper blade, at a point behind the pivot point, to the perimeter of a rotatable member. The rotatable member is designed to roll on a flat surface, and as it does so, moves the lever and causes oscillation of the upper blade.
Page, U.S. Pat. No. 2,376,002, discloses a cutter for sprouts or tree suckers. When the branch to be cut is placed between the blades, the cutter is hung downwardly. A handle 22 is pulled down, moving down a rod 20 which is attached to an extension from a movable blade 13. The extension from the movable blade 13 is positioned rearwardly from the pivot point of the movable blade. Thus, downward movement of the handle 22 causes pivoting of the movable blade.
None of the cutting devices known to Applicants disclose or suggest a trigger actuated scissor device with a handle which extends at an acute angle to the axis of the blades and transverse to the pivot axis of the blades, having a pivotal lever connecting the trigger and the movable blade, wherein the lever engages the movable blade at a point forwardly of the pivot point of the blades. A scissor device with such a configuration can have a lower axial dimension considerably less than that of the Seeberger device, and still provide enough leverage at the trigger so that the operator can pivot the upper blade and cut through thick or difficult to cut material.
Further, none of the known scissor devices disclose or suggest a trigger mechanism in a handle which is actuated by sliding the trigger substantially transversely to the axis of the handle. Such a mechanism is easy for the operator to manipulate.